Nest Js: Webscoket Reverse proxy - node.js

Question

I created a graphql subscription server which runs on port 7777 with the path /subscriptions/graphql for both HTTP, WebSocket protocol which is absolutely working fine when I directly used the URL with other services.
HTTP : http://localhost:7777/subscriptions/graphql
websocket: ws://localhost:7777/subscriptions/graphql
Subscription server is a microservices just like the other services we have. Now my aim is to do a reverse proxy in the gateway. I wanted to do a reverse proxy for both HTTP, WebSocket based connections.
For this, I wrote two middleware one for HTTP and one for Websocket. Http based middleware is working fine. Whereas the WebSocket is not working as expected.
Websocket based Middileware
import { NestMiddleware, Logger, Injectable } from '#nestjs/common';
import { createProxyMiddleware } from 'http-proxy-middleware';
#Injectable()
export class SubscriptionServiceWebSocketReverseProxyMiddleware
implements NestMiddleware {
/*
jscpd:ignore-start
*/
constructor(private readonly logger: Logger) { }
private proxy = createProxyMiddleware({
target: 'ws://localhost:7777/subscriptions/graphql',
secure: false,
changeOrigin: true,
ws: true,
onProxyReq: (proxyReq, req, res) => {
this.logger.debug(
`[SubscriptionServiceWebSocketReverseProxyMiddleware]: Proxying ${req.method} request originally made to '${req.originalUrl}'...`,
);
},
});
use(req: any, res: any, next: () => void) {
this.proxy(req, res, next);
}
/*
jscpd:ignore-end
*/
}
When the websocket request made from UI, I am getting below error
[Nest] 43743 - 08/24/2020, 3:20:20 PM [SubscriptionServiceWebSocketReverseProxyMiddleware]: Proxying GET request originally made to '/subscriptions/ws/graphql'...
[HPM] Upgrading to WebSocket
events.js:200
throw er; // Unhandled 'error' event
^
Error: read ECONNRESET
at TCP.onStreamRead (internal/stream_base_commons.js:200:27)
Emitted 'error' event on Socket instance at:
at emitErrorNT (internal/streams/destroy.js:92:8)
at emitErrorAndCloseNT (internal/streams/destroy.js:60:3)
at processTicksAndRejections (internal/process/task_queues.js:81:21) {
errno: 'ECONNRESET',
code: 'ECONNRESET',
syscall: 'read'
}
Note: I was able to see the log message inside the middleware which means there is no issue with middleware. I also see the subscription service alone is working as well.